how do i change 24 fps to 60 fps without affecting the speed?
There is a time remapping option to remap your speed under the Render Dimension panel:

After the remapping, you need to calculate the end time by your self.
And also, you can directly &quot;scale&quot; the animation inside your time line as you do in 3D View (press s). As 24 to 60, press 2.5 in your numpad should give you a correct result
The keyframe and animation is kind of complicate and give various option to tweak and customize the result. Give it a try and if still having problem, list more detail on what you've encountered with clear figure or good structured text description.